Biofilter

Common uses include processing waste water, capturing harmful chemicals or silt from surface runoff, and microbiotic oxidation of contaminants in air.

Industrial biofiltration can be classified as the process of utilizing biological oxidation to remove volatile organic compounds, odors, and hydrocarbons.

Since the early 1990s, engineered biofilters have provided significant footprint reductions over the conventional flat-bed, organic media type.

Several companies offer these types of proprietary packing materials and multi-year guarantees, not usually provided with a conventional compost or wood chip bed biofilter.

Although widely employed, the scientific community is still unsure of the physical phenomena underpinning biofilter operation, and information about the microorganisms involved continues to be developed.

[2] A biofilter/bio-oxidation system is a fairly simple device to construct and operate and offers a cost-effective solution provided the pollutant is biodegradable within a moderate time frame (increasing residence time = increased size and capital costs), at reasonable concentrations (and lb/hr loading rates) and that the airstream is at an organism-viable temperature.

Media irrigation water, although many systems recycle part of it to reduce operating costs, has a moderately high biochemical oxygen demand (BOD) and may require treatment before disposal.

However, this "blowdown water", necessary for proper maintenance of any bio-oxidation system, is generally accepted by municipal publicly owned treatment works without any pretreatment.

Biofilters are being utilized in Columbia Falls, Montana at Plum Creek Timber Company's fiberboard plant.

[5] Biological treatment has been used in Europe to filter surface water for drinking purposes since the early 1900s and is now receiving more interest worldwide.

A biofilter is a bed of media on which microorganisms attach and grow to form a biological layer called biofilm.

Air or water flows through a media bed and any suspended compounds are transferred into a surface biofilm where microorganisms are held to degrade pollutants.

[5] Most biofilters use media such as sand, crushed rock, river gravel, or some form of plastic or ceramic material shaped as small beads and rings.

Depending on the type of application and on the media used for microbial growth, bioclogging can be controlled using physical and/or chemical methods.

Such techniques include qPCR (quantitative polymerase chain reaction), ATP assay, metagenomics, and flow cytometry.

[19] In this context, a biofilter located after a septic tank constitutes a robust process able to sustain the variability observed without compromising the treatment performance.

In anaerobic wastewater treatment facilities, biogas is fed through a bio-scrubber and “scrubbed” with activated sludge liquid from an aeration tank.